For me, it's been the opposite. I really didn't start turning out what I would consider to be "quality work" until I was about 55 (I'm 66 now). Not saying that I'm a particularly great fabricator, carpenter, concrete finisher, or whatever now, but it took me that long to learn techniques (tricks of the trade type stuff) to feel relatively confident (and competent).
Another BIG part of it was that, as I got older, I was able to obtain the tools and equipment that allows me to perform better work. In fact, to be honest, that's probably about 90% of my improvement.